通过div嵌套实现阴影，有两个边能有阴影效果

<style>
.shadow{
width:670px;
position: relative;
left: 3px;
top: 3px;
margin-right: 3px;
margin-bottom: 3px;
}

.shadow2,
.shadow3,
.scontent {
width:670px;

position: relative;
left: -1px;
top: -1px;
}
.shadow1 {
background: #F1F0F1;
}
.shadow2 {
background: #DBDADB;
}
.shadow3 {
background: #B8B6B8;
}
.scontent {
background: #ffffff;
border: 1px solid #848284;
}
</style>



XHTML部分：
<div class="shadow">
<div class="shadow1">
<div class="shadow2">
<div class="shadow3">
<div class="scontent">
kingisking
</div>
</div>
</div>
</div>
</div>

效果如下：